Folding support for seats, table plates, and the like



Aug. 18. 1925. 1,550,283

M. SCHMIDT FOLDING SUPPORT FOR SEATS, TABLE PLATES AND THE LIKE Filed Feb. .6. 1923 Patented Aug. 18, 1925.

UNITED STATES PATENT OFFICE.

MAX SCHMIDT, OF BERLIN, GERMANY, ASSIGNOR, TO THE FIRM I'bGEL & SCHMIDT,

0F IBERLIN-WILMERSDORF, GERMANY.

FOLDING SUPPORT FO'R SEATS,

Application filed February To all whom it may concern:

Be it known that I, MAX SCHMIDT, a citizen of the German Republic, residing at Berlin, Germany, have invented certain new and useful Improvements in Folding Supports for Seats, Table Plates, and the like (for which an application for patent has been filed in Germany on the 6th of February, 1922, Patent No. 366,111), of which the following is a specification.

This invention relates to a folding support for seats, table plates, telescopes, photographic cameras and the like which is composed of stays for the seat or plate and of stays serving as feet, all the stays being articulated like shears. Folding stands for camp stools have become known already in which the stays are alternately mounted in two elements loosely guided upon said stays and adapted to be mutually moved, so that when said elements are being moved the one towards the other the folding stand is spread out, the stays being folded up when the elements-are moved theone away from the other.

This invention has for its object to increase the stability of folding stands of this type and further the security. against accidental folding up. With this object in view the elements movable on the stays and acting upon said stays consist of two mas sive plane plates which, when the folding stand is in the spread out position of use, are in contact the one with the other upon their entire opposite faces so that tilting or shaking of the stand is absolutely prevented. The ends of the stays fit accurately into cavities of the movable elements which cavities serve as thrust bearings and the ends of the stays are secured in these cavities by means of bolts which traverse the movable elements or plates. Owing to this arrangement of the parts the compressive stress which occurs when the camp stool is being used is well compensated and directly intercepted by the massive plates. As the two plates are automatically locked when they are in contact with one another they form together a very strong block like supporting body. I

In order to make the invention clearly understood, I shall hereinafter proceed to describe the same with reference to the camp-stool shown by way of example on the acc mpanying d awing, wherein TABLE PLATES, AND THE LIKE.

s, 1923. Serial No. 617,393.

Fig. 1 shows the camp stool ready for use.

Fig. 2 shows the camp stool folded up.

Fig. 3 shows on a larger scale in plan view the upper supporting disk, the upper stays being shown'in section.

Fig. 4: shows the lower supporting disk 1n'a plan View from underneath, the foot stays being shown in section.

Fig. 5 is a vertical section on'line A-B of Fig. 3, the supporting disks being some distance apart.

Fig. 6 is a section on line CD of Fig. :0 the supporting disksbeing in close conact.

The folding camp stool shown on the drawing comprises four stays a for the seat and four foot stays'b. Two massive diskshaped supporting platesc and (Z are movably arranged on said stays a and 6. The foot stays Z) are pivotally mounted on the upper supporting disk 0, the seat stays a being guided with sufficient play in slots 6 of the upper supporting disk 0 which extend radially in outward direction. The slots 6 are inclined as shown in Fig. 5.

The foot stays b are pivotally fixed in the upper supporting plate 0 by means of screw bolts f inserted from above into holes of the disk and having lugs g at the lower ends in which said foot stays b are pivotally fixed. The upper ends of the stays Z1 engage with cavities in the supporting plate 0, said cavities serving as thrust bearings. Nuts 72. screwed upon the upper ends of the bolts f serve to secure the same in position and to securely connect the stays b with. the supporting plate 0. The seat or upper stays a which are loosely guided in the upper sup porting disk 0 are displaced 45 with regard to the foot stays b in order to improve the stability of the camp stool and to avoid interference between the bearing points and slots in the supporting plate;

The lower supporting disk d is essentially similar to the upper supporting disk, the upper or seat stays a being pivotally mounted in this lower disk at and the foot stays 7) being guided with play in slots of said disk. The bearing points for the seat stays and the slots for the foot stays are arranged and constructed in the manner as described with reference to the upper supporting disk. The seat stays a have hooks a at the upper ends to which the seat is attached if the support is in the unfoldedposition (Fig. 1). The foot stays b have at their lower ends shoes Z designed to ensure a greater stability of the folding support.

The ends of the stays; are of semi-spherical shape as shown in Fig. 5 and engage with cavities of the massive disk-shaped plate 0 which cavities are of corresponding shape so that these two elements act like ball-joints and whatever may be the position of the stays whether folded together or pulled out the pressure is always intercepted by said disk-shaped plates.

(living to the special mounting and guiding of the stays in the two movable supporting disks the stays will be spread out like shears when said supporting disks are moved the one towards the other but folded together to form a bundle when the supporting disks are moved a-ii ay the one from the other.

If the support is in unfolded position the plane inner faces of the two supportin disks 0, (Z are in close contact the one witi the other and support each othen whereby tilting or shaking of the camp stool is avoided. As the stays a and b engage with the cavities of the supporting plates 0, ml which act like thrust bearings the compressive stress is directly transferred to the massive supporting plates. In this; contact position the supporting disks may be locked together with the aid of convenient means in order to secure the supportin the unfolded position and to prevent any accidental collapsing of the support.

In the form of construction shown the locking ofthe supporting disks is auto1nati- Cally effected by spring action as soon as the disks come in cont-act the one with the other.

With this object in view a lever-like double pawl m is arranged upon the upper supporting disk 0' pi'votable around the screw A spring 0 wound around the shaft of screw or serves to hold the pawl normally in contact with a pin 79- if two bores q of the upper supporting disk 0 are partly covered by lid pawl. Two'pins r registering with the bores g of the upper disk 0 and fixed upon the lower supporting disk d have each a groove or notch s and a bevelled head t (Fig. 6).

W'hen the supporting disks come in contact the pins 7"- of the lower disk penetrate into the bores g of the upper disk and their heads 5 push the pawl m aside against the action of the spring until the notches s of pins r register with the pawl m. At this in.- stant the pawl m is forced by the action. of the spring to engage with said notches s and locks the supporting plates together so that they. form one block-like body. Tofold the support it is necessary to unlock the locking device this being easily eiiiected by lifting the pawl m, out of the notches s with the aid of the curved end a of the pawl which serves as handl'e.

The improved folding support. 021111 be used not only for camp stools but also: for camp tables, as substitute for tripods and for sinril'ar purposes.

In. a folding stand for camp stools: of the type described, the means for locking the stays in the unfolded spread, out position con-rprising in combination. with an upper supportingplate having two. verticalbores, and with a lower supportingplate, a spring controlled double pawlpivotally mounted intermediate its ends on said upper sup porting disk, two pins having'eacha notch in its shaft fixed upon said lower supporting disk which registerwith saidi bores of the upper supporting disk and penetrate through the same when said disks are brought in contact the one with the other, and a bevelled head of each pin: designed to push aside said double pawl until the same isforced by its springto engage with said notches of the pin, substantially as de scrihed and shown and for the purpose set forth.

In testimony whereof I afiix: mysignature; 

